Effect of Flap Design for Enamel Matrix Derivative Application in Intraosseous Defects.

OBJECTIVE: To systematically review the literature addressing the focused question: What is the effectiveness of different surgical and nonsurgical procedures combined with enamel matrix derivative (EMD) on clinical, radiographic, and patient-centered outcomes in intraosseous defects? METHODS: Electronic (Medline, Scopus, and Cochrane databases) and hand literature searches were performed for studies including at least 1 treatment arm where EMD had been applied according to 1 of the following procedures: modified Widman flap; papilla preservation variants (PPVs), including papilla preservation technique, modified papilla preservation technique, and simplified papilla preservation technique; minimally invasive variants, including minimally invasive surgical approach and minimally invasive surgical technique; single-flap variants (SFVs), including single-flap approach and modified minimally invasive surgical technique; or nonsurgical application (flapless approach). Data from 42 selected articles were used to perform a network meta-analysis, and a hierarchy of surgical and nonsurgical applications of EMD was built separately for EMD and EMD + graft based on 6- to 12-mo clinical and radiographic outcomes. RESULTS: Among surgical approaches, EMD was associated with best regenerative outcomes when applied through SFVs, with a mean clinical attachment level gain of 3.93 mm and a reduction in the intrabony component of the defect of 3.35 mm. For EMD + graft, limited differences in regenerative outcomes were observed among surgical procedures. PPVs were associated with the highest residual probing depth for EMD (4.08 mm) and EMD + graft (4.32 mm). CONCLUSIONS: In the treatment of periodontal intraosseous defects, 1) SFVs appear to optimize the regenerative outcomes of EMD; 2) substantial regenerative outcomes can be obtained with SFVs and conservative double flaps (i.e., PPVs and minimally invasive variants) when EMD is combined with a graft; and 3) residual probing depth was higher following PPVs for EMD and EMD + graft. KNOWLEDGE TRANSFER STATEMENT: The results of the present systematic review and meta-analysis can be used by clinicians to identify the most effective surgical or nonsurgical procedure to treat an intraosseous defect with EMD or EMD + graft. The main findings indicate that when EMD application is indicated, surgical access based on a single flap seems the most appropriate to optimize clinical outcomes. The application of EMD + graft can be effectively combined with single flaps and conservative double flaps.

Periodontal education and assessment in the undergraduate dental curriculum-A questionnaire-based survey in European countries.

OBJECTIVES: This survey aimed to evaluate whether periodontal education and assessment in undergraduate dental curricula amongst the member countries of the European Federation of Periodontology (EFP) follow the competency-based curricular guidelines and recommendations developed by the Association for Dental Education in Europe. MATERIALS AND METHODS: A multiple-choice questionnaire was emailed to 244 dental institutes amongst the 24 EFP member countries between November 2014 and July 2015. RESULTS: Data were received from 16 (66.7%) EFP member countries. Out of 117 responding dental institutes, 76 (64.95%) were included as valid responders. In most of the institutes (86.3%), a minimum set of competencies in periodontology was taken into account when constructing their dental education programmes. Out of 76 responders, 98.1% included lecture-based, 74.1% case-based and 57.1% problem-based teaching in their periodontal curricula, whilst a minority (15.9%) also used other methods. A similar pattern was also seen in the time allocation for these four educational methods, that is, the highest proportion (51.8%) was dedicated to lecture-based teaching and only a small proportion (5.7%) to other methods. Periodontal competencies and skills were most frequently assessed by clinical grading on clinic, multiple-choice examination (written examination) and oral examination, whereas competency tests and self-assessment were rarely used. Only in 11 (14.5%) cases, access flap procedures were performed by students. CONCLUSION: Great diversity in teaching methodology amongst the surveyed schools was demonstrated, and thus, to harmonise undergraduate periodontal education and assessment across Europe, a minimum set of recommendations could be developed and disseminated by the EFP.

Effect of dynamic three-dimensional culture on osteogenic potential of human periodontal ligament-derived mesenchymal stem cells entrapped in alginate microbeads.

BACKGROUND AND OBJECTIVE: Bioreactors are devices that efficiently create an environment that enables cell cultures to grow in a three-dimensional (3D) context mimicking in vivo conditions. In this study, we investigate the effect of dynamic fluid flow on the osteogenic potential of human mesenchymal stem cells obtained from periodontal ligament and entrapped in alginate microbeads. MATERIAL AND METHODS: After proper immunophenotyping, cells were encapsulated in barium alginate, cultured in 3D static or 3D dynamic conditions represented by a bioreactor system. Calcein-AM/propidium iodide staining was used to assess cellular viability. Quantitative real-time polymerase chain reaction was used to analyze the expression of osteogenic markers (Runx2 and COL1). Alizarin Red S staining and the Fourier transform infrared spectroscopy were used to assess mineral matrix deposition. RESULTS: Optimal encapsulation procedure, in terms of polymer pumping rate, distance from droplet generator to the gelling bath and atomizing airflow was assessed. Cell viability was not affected by encapsulation in alginate microbeads. Bioreactor cell exposure was effective in anticipating osteogenic differentiation and improving mineral matrix deposition. CONCLUSION: For the first time human mesenchymal stem cells obtained from periodontal ligaments encapsulated in alginate microbeads were cultured in a bioreactor system. This combination could represent a promising strategy to create a cell-based smart system with enhanced osteogenic potential useful for many different dental applications.

A review of factors influencing the incidence and severity of plaque-induced gingivitis.

An individual variation in the gingival inflammatory response to the dental biofilm has been demonstrated. This variability can be observed between individuals with neither quantitative nor qualitative differences in plaque accumulation. The reported significant differences in gingival inflammatory response under quantitatively and/or qualitatively almost identical bacterial challenge suggest that the gingival response to plaque accumulation may be an individual trait, possibly genetic in origin. The most recent classification of periodontal diseases acknowledges that the clinical expression of plaque-induced gingival inflammation can be substantially modified by systemic factors, either inherent to the host or related to environmental influences. The aim of the present literature review is to describe (i) the factors influencing the development of plaque-induced gingivitis as well as (ii) those metabolic, environmental and systemic factors which have a direct impact on the etiopathogenetic pathway of plaque-induced gingivitis, thus altering the nature or course of the gingival inflammatory response to dental biofilm.

Efficacy of triclosan-based toothpastes in the prevention and treatment of plaque-induced periodontal and peri-implant diseases.

AIM: To evaluate the efficacy of triclosan (T)-based toothpaste formulations in the prevention and treatment of plaque-induced periodontal and peri-implant diseases. METHODS: A review of the existing literature was conducted with a systematic approach in order to retrieve pertinent articles. RESULTS AND CONCLUSIONS: i) Compared with a control fluoride dentifrice, a fluoride dentifrice containing T formulations provides a more effective level of plaque control and gingival health in patients affected by gingivitis; ii) 0.3% T/2% copolymer/0.243% NaF formulation and 0.3% T/0.13% Ca glicerophosphate/1000 ppm F toothpaste in a natural Ca carbonate base seem the most effective T-based toothpaste formulations in controlling plaque and gingival inflammation in patients with gingivitis or mild/moderate periodontitis over a 6-month period; iii) 0.3% T/2% copolymer/0.243% NaF toothpaste formulation can reduce clinical attachment loss in young adolescents when compared with a 0.243% NaF toothpaste formulation, the magnitude of the difference being greater for patients with deep periodontal pockets at baseline; iv) 0.3% T/2% copolymer/0.243% NaF toothpaste formulation is either similarly or more efficacious in preventing the progression/recurrence of periodontal destruction when compared to a conventional fluoride toothpaste; v) 0.3% T/2% copolymer/0.243% NaF toothpaste formulation seems to be more effective than a fluoride toothpaste formulation in controlling the severity of mucosal inflammation, the incidence of mucosal bleeding as well as reducing probing pocket depth around dental implants.

Gene--gene interaction among cytokine polymorphisms influence susceptibility to aggressive periodontitis.

Aggressive periodontitis (AgP) is a multifactorial disease. The distinctive aspect of periodontitis is that this disease must deal with a large number of genes interacting with one another and forming complex networks. Thus, it is reasonable to expect that gene-gene interaction may have a crucial role. Therefore, we carried out a pilot case-control study to identify the association of candidate epistatic interactions between genetic risk factors and susceptibility to AgP, by using both conventional parametric analyses and a higher order interactions model, based on the nonparametric Multifactor Dimensionality Reduction algorithm. We analyzed 122 AgP patients and 246 appropriate periodontally healthy individuals, and genotyped 28 polymorphisms, located within 14 candidate genes, chosen among the principal genetic variants pointed out from literature and having a role in inflammation and immunity. Our analyses provided significant evidence for gene--gene interactions in the development of AgP, in particular, present results: (a) indicate a possible role of two new polymorphisms, within SEPS1 and TNFRSF1B genes, in determining host individual susceptibility to AgP; (b) confirm the potential association between of IL-6 and Fc γ- receptor polymorphisms and the disease; (c) exclude an essential contribution of IL-1 cluster gene polymorphisms to AgP in our Caucasian-Italian population.

Effect of hydroxyapatite-based biomaterials on human osteoblast phenotype.

The present study evaluated human primary osteoblasts and two different osteoblast-like cell lines behaviour when cultured in presence of different hydroxyapatite-based (HA) biomaterials (SINTlife-FIN-CERAMICA S.p.a., Faenza, Italy; Bio-Oss, Geistlich Biomaterials, Woulhusen, Switzerland; Biostite-GABA Vebas, San Giuliano Milanese, MI, Italy), focusing attention on the effect of HA/Biostite in terms of modulation of osteoblastic differentiation. Analysis were about adhesion, proliferation and mineralization activity. Runt-related transcription factor 2 (Runx2), Estrogen Receptor alpha (ERalfa) expression and alkaline phosphatase activity (ALP) were measured as osteoblastic differentiation markers. Determination of viable cells was done with MTT colorimetric assay. Scanning electron microscopy (SEM) analysis was performed on biomaterial-treated cells. All hydroxyapatite-based biomaterials didn't affect cells morphology and viability, whereas only presence of HA/Biostite improved cells adhesion, growth and differentiation. Adhesion and spreading of the primary cells on HA/Biostite were the same showed by two different osteoblast-like cell lines. These results have important implications for both tissue-engineered bone grafts and enhancement of HA implants performance, to develop new teeth's supporting structure therapies and replacement.

Effect of smoking status on pocket probing depth and bleeding on probing following non-surgical periodontal therapy.

AIM: Cigarette smoking is a risk factor for periodontitis incidence and progression. Contrasting results were obtained when the impact of cigarette smoking on the clinical outcomes of non-surgical periodontal therapy (NSPT) was evaluated. The present study was designed to evaluate the smoking status as outcome determinant of NSPT. METHODS: Two groups of patients with different smoking status (smoker group, S, and non-smoker group, NS) were retrospectively selected from a pool of patients seeking care for periodontitis. The effectiveness of NSPT was assessed by evaluating the changes in 1) the prevalence of sites with different pocket probing depth (PPD), and 2) the patient- and site-specific bleeding. RESULTS: Group S comprised of 65 patients (mean age: 45.6+/-8.7 years; 24 males and 41 females) and group NS comprised of 66 patients (mean age: 46.8+/-11.7 years; 17 males and 49 females). A statistically significant increase in the prevalence of sites with PPD< or =3 mm (P<0.000), as well as a significant decrease in the prevalence of sites with PPD 4/6 mm (P<0.000) and PPD> or =7 mm (P< or =0.01) was detected at re-evaluation. BoP scores were significantly reduced for the entire dentition (P<0.000) as well as for sites with PPD< or =3 mm (P<0.01) and PPD 4/6 mm (P<0.000) in both group S and group NS. No statistically significant differences in the post treatment change of PPD and BoP scores were detected between groups. CONCLUSION: Our results seem to suggest that smoking status has a limited, if any, effect on the clinical outcomes of NSPT.

IL-1 gene cluster is not linked to aggressive periodontitis.

The interleukin-1 (IL-1) gene family has been associated with susceptibility to periodontal diseases, including aggressive periodontitis (AgP); however, the results are still conflicting. The present study investigated the association between IL-1 genes and AgP using 70 markers spanning the 1.1-Mb region, where the IL-1 gene family maps, and exploring both the linkage disequilibrium (LD) and the haplotype structure in a case-control study including 95 patients and 121 control individuals. No association between AgP and IL1A, IL1B, and IL1RN genes was found in either single-point or haplotype analyses. Also, the LD map of the region 2q13-14 under the Malécot model for multiple markers showed no causal association between AgP and polymorphisms within the region (p = 0.207). In conclusion, our findings failed to support the existence of a causative variant for generalized AgP within the 2q13-14 region in an Italian Caucasian population.

Recolonization of the oral cavity by Streptococcus mutans after a combined mechanical/chemical antisepsis protocol.

AIM: The bacterial colonization of teeth by Streptococcus mutans (StrepM) represents a major risk factor for the development of dental caries. At present, no clinical studies have explored the effect of a combined mechanical-chemical antisepsis protocol in a periodontally-healthy population and the pattern of recolonization of StrepM in subjects whose StrepM infection was successfully eradicated. The present study was designed in order to 1) determine the salivary and plaque changes in StrepM content after a combined mechanical/chemical antisepsis protocol; and 2) evaluate the pattern of recolonization when StrepM was successfully eradicated from saliva and plaque. METHODS: Thirty-five periodontally-healthy and caries-susceptible subjects successfully entered and concluded the study. At baseline, non-surgical periodontal therapy was performed according to the principles of full mouth disinfection. Adjunctive home-based rinsing with a 0.2% chlorhexidine mouthrinse was requested for the following week. StrepM concentration was assessed in saliva and plaque at the initial contact appointment, at baseline, and 1-week, 1-month, 3-month and 6-month follow-up. RESULTS: A significant effect of ''time'' on StrepM concentration in saliva and plaque was observed (P<0.000). In subjects with successful eradication of StrepM at 1 week (N=17 plaque samples), StrepM infection recurrence occurred within 3-6 months. CONCLUSION: The results of the present study demonstrated that 1) the application of the investigated mechanical/chemical antisepsis protocol can effectively reduce StrepM colonies in saliva and plaque of periodontally healthy subjects; and 2) in plaque samples, StrepM infection recurrence tends to occur within 3-6 months.

Comparison between two methods for periodontal risk assessment.

AIM: Risk assessment is increasingly important in periodontology. The aim of this article was to propose a new objective method (UniFe) in order to simplify the risk assessment procedures. UniFe was compared with a computer-based risk assessment tool (PAT(R)). METHODS: Risk scores for both UniFe and PAT(R) were calculated for 107 patients, randomly selected among patients seeking care at a specialist periodontal clinic. For UniFe risk calculation, the ''parameter scores'' assigned to smoking status, diabetic status, number of sites with probing depth 5 mm, bleeding on probing score (BoP) and bone loss/age, were added and the sum was referred to a ''risk score'', ranging from 1 (low risk) to 5 (high risk). PAT(R) generated a risk score on a scale from 1 (lowest risk) to 5 (highest risk). RESULTS: The mean UniFe and PAT(R) risk scores were 4.5+/-0.9 and 4.6+/-0.7, respectively. Cohen k-statistics amounted to 0.7, suggesting a good agreement between methods. Difference in risk score between methods was significantly explained by the parameter scores of BoP and bone loss/age (adjusted R2=0.378). CONCLUSION: The comparison between UniFe and PAT(R) demonstrated a good level of agreement between methods in a randomly selected population referred to a periodontal clinic.

Effects of a hydroxyapatite-based biomaterial on gene expression in osteoblast-like cells.

Biostite is a hydroxyapatite-derived biomaterial that is used in periodontal and bone reconstructive procedures due to its osteoconductive properties. Since the molecular effects of this biomaterial on osteoblasts are still unknown, we decided to assess whether it may specifically modulate osteoblast functions in vitro. We found that a brief exposure to Biostite significantly reduced the proliferation of MG-63 and SaOS-2 osteoblast-like cells to approximately 50% of the plateau value. Furthermore, gene array analysis of MG-63 cells showed that Biostite caused a differential expression of 37 genes which are involved in cell proliferation and interaction, and related to osteoblast differentiation and tissue regeneration. Results were confirmed by RT-PCR, Western blot, and by an increase in alkaline phosphatase (ALP) specific activity. Biostite also increased levels of polycystin-2, a mechano-sensitive Ca(2+) channel, a promising new marker of bone cell differentiation. Biostite, therefore, may directly affect osteoblasts by enhancing chondro/osteogenic gene expression and cytoskeleton-related signaling pathways, which may contribute to its clinical efficacy.

Linkage disequilibrium analysis of case-control data: an application to generalized aggressive periodontitis.

Several studies have shown a role for the involvement of interleukin (IL)-1 gene cluster polymorphisms in the risk of periodontal diseases. In the present study, we tested polymorphisms, derived from genes of the IL-1 cluster, for association with generalized aggressive periodontitis (GAP) through both allelic association and by constructing a linkage disequilibrium (LD) map of the 2q13-14 disease candidate region. The IL-1RN (VNTR) genotype distribution observed was significantly different in GAP and control subjects (P=0.019). We also observed some evidence for an association between GAP and the IL-1B(+3953) polymorphism (P=0.039). The pattern of association in the region, represented as an LD map, identifies a recombination hot area between the IL-1B(+3953) and IL-1B(-511) polymorphisms. Multilocus modelling of association with disease gives a location for the peak association at the IL-1B(+3953) marker, although support for the peak is not significant. Haplotype analysis identifies a IL-1B(+3953)-IL-1B(-511) haplotype as having the lowest P-value in the region. Recognition of the presence of a recombination hot area between the IL-1B(+3953) and IL-1B(-511) polymorphisms will have an important bearing on future efforts to develop higher resolution SNP analysis in this region for both this and other diseases for which this cluster is implicated.

Modulation of clinical expression of plaque-induced gingivitis: effect of incisor crown form.

Evidence indicates that incisor crown form correlates with clinical periodontal features. It was hypothesized that incisor crown form may explain subject differences in gingivitis expression. The present experimental gingivitis study aimed to assess the effect of incisor crown form on plaque accumulation and gingival inflammation, and on individual susceptibility to plaque-induced gingivitis. Eighty-five periodontally healthy subjects were evaluated. A negative correlation was found between incisor crown width/crown length ratio and bleeding score (p = 0.045). From the 85 subjects, two groups of subjects with either 'long-narrow' or 'short-wide' incisor form were identified. The 'long-narrow' group had a significantly higher bleeding score than the 'short-wide' group (p = 0.014). No significant differences were found in the incisor crown width/crown length ratio between previously identified 'high responder' and 'low responder' subjects (Trombelli et al., 2004a). In conclusion, incisor crown form appears to affect the bleeding response of inflamed gingival tissues, while it exerts no influence on explaining differences in individuals' susceptibility to plaque-induced gingivitis.

Periodontal diseases: current and future indications for local antimicrobial therapy.

The microbial etiology of gingivitis and periodontitis provides the rationale for use of adjunctive antimicrobial agents in the prevention and treatment of periodontal diseases. Although mechanical removal of supra- and subgingival calcified and non-calcified plaque deposits has been proved effective to control the gingival inflammatory lesions as well as to halt the progression of periodontal attachment loss, some patients may experience additional benefits from the use of systemic or topical antimicrobial agents. Such agents are able to significantly affect supra- and subgingival plaque accumulation and/or suppress or eradicate periodontal pathogenic microflora. Currently, properly selected local antiseptic and systemic antibiotic therapies can provide periodontal treatment that is generally effective, low-risk and affordable. This paper will briefly review the host-related conditions in which the periodontal preventive and therapeutic approaches may be effectively assisted by a local antimicrobial regimen. Potential future indications for adjunctive local antimicrobial therapy will also be discussed.

Response to a plaque control regimen on different levels of gingival inflammation.

BACKGROUND: The purpose of the present study was to evaluate the effectiveness of an oral hygiene regimen in subjects presenting with substantially different severity of plaque-associated gingivitis. METHODS: The study population was selected from among a large pool of subjects undergoing an experimental gingivitis trial. At completion of the 21-day plaque accumulation period, 2 sub-groups of subjects were identified on the basis of uppermost and lowest quartile for Gingival Index (GI), respectively classified as highly-inflamed (Hinf; n=17; GI: 1.07+/-0.10) and slightly-inflamed (Sinf; n=22; GI: 0.28+/-0.09) groups. An oral hygiene regimen, based on use of amine fluoride/stannous fluoride-containing toothpaste and mouthrinse, was then prescribed for 21 days. RESULTS: Plaque Index (PI), GI, gingival crevicular fluid (GCF) and Angulated Bleeding Index (AngBI) significantly decreased after treatment in both HInf and SInf groups (p<0.001). However, PI (0.77+/-0.41 vs 0.43+/-0.33, p<0.01), GI (0.23+/-0.30 vs 0.08+/-0.11, p<0.05), GCF (15.23 +/-7.11 vs 7.66+/-2.93, p<0.0000) remained significantly greater in the Hinf group compared to the Sinf group. CONCLUSIONS: These results suggest that 1) an oral hygiene regimen based on amine/stannous fluoride-containing toothpaste and mouthrinse is effective in reducing plaque-associated gingivitis, regardless of pre-existing severity of gingival inflammation; 2) the level of improvement in gingival status, however, is dependent on the pre-existing severity of the inflammatory condition.

A systematic review of the effect of surgical debridement vs non-surgical debridement for the treatment of chronic periodontitis.

OBJECTIVE: To systematically review the evidence of effectiveness of surgical vs. non-surgical therapy for the treatment of chronic periodontal disease. METHODS: A search was conducted for randomized controlled trials of at least 12 months duration comparing surgical with non-surgical treatment of chronic periodontal disease. Data sources included the National Library of Medicine computerised bibliographic database MEDLINE, and the Cochrane Oral Health Group (COHG) Specialist Trials Register. Screening, data abstraction and quality assessment were conducted independently by multiple reviewers (L.H., F.H., L.T.). The primary outcome measures evaluated were gain in clinical attachment level (CAL) and reduction in probing pocket depth (PPD). RESULTS: The search provided 589 abstracts of which six randomized controlled trials were included. Meta-analysis evaluation of these studies indicated that 12 months following treatment, surgical therapy resulted in 0.6 mm more PPD reduction (WMD 0.58 mm; 95% CI 0.38, 0.79) and 0.2 mm more CAL gain (WMD 0.19 mm; 95% CI 0.04, 0.35) than non-surgical therapy in deep pockets (>6 mm). In 4-6 mm pockets scaling and root planing resulted in 0.4 mm more attachment gain (WMD -0.37 mm; 95% CI -0.49, -0.26) and 0.4 mm less probing depth reduction (WMD 0.35 mm; 95% CI 0.23, 0.47) than surgical therapy. In shallow pockets (1-3 mm) non-surgical therapy resulted in 0.5 mm less attachment loss (WMD -0.51 mm; 95% CI -0.74, -0.29) than surgical therapy. CONCLUSIONS: Both scaling and root planing alone and scaling and root planing combined with flap procedure are effective methods for the treatment of chronic periodontitis in terms of attachment level gain and reduction in gingival inflammation. In the treatment of deep pockets open flap debridement results in greater PPD reduction and clinical attachment gain.

Intra- and inter-examiner reproducibility in keratinized tissue width assessment with 3 methods for mucogingival junction determination.

BACKGROUND: Although the need for "adequate" amount of keratinized tissue (KT) for periodontal health is questionable, the mucogingival junction (MGJ) often serves as a measurement landmark in periodontal evaluations. Limited information is available on the reproducibility of KT width (KTW) assessment. The purpose of this study was to assess intra- and inter-examiner reproducibility in measuring KTW by using 3 different methods to identify MGJ location. METHODS: Fifteen patients provided 17 teeth which had undergone a gingival augmentation procedure (connective tissue graft; surgery group) and an equal number of contralateral, non-treated teeth (control group). At the midbuccal aspect of each tooth, KTW was assessed by 2 independent examiners after MGJ identification by the visual (VM), functional (FM), and visual with histochemical staining (HM) method. Data analysis was based on intra-class correlation coefficients (ICC) and 3-way analysis of variance (ANOVA) for differences between replicate measurements. RESULTS: KTW was significantly different between treated and control teeth. No significant differences in KTW were found in relation to method for MGJ determination and examiner. Intra- and inter-examiner reproducibility was high, regardless of treatment status or method for MGJ determination (ICC = 0.92 - 0.99). Standard deviations of the difference between replicate measurements ranged from 0.46 mm for VM to 0.21 mm for HM. CONCLUSIONS: Intra- and inter-examiner reproducibility has been shown to be substantially consistent when different methods for MGJ determination are used to measure the apico-coronal dimension of the gingiva. The level of reproducibility does not seem to be affected whether or not the mucogingival complex has been surgically altered by a gingival augmentation procedure.

Cigarette smoking negatively affects healing response following flap debridement surgery.

BACKGROUND: The purpose of the present parallel design, controlled clinical trial was to evaluate the treatment outcome following flap debridement surgery (FDS) in cigarette smokers compared to non-smokers. METHODS: After initial therapy, 57 systemically healthy subjects with moderate to advanced periodontitis who presented with one area (at least 3 teeth) where surgery was required were selected. Twenty-eight patients (mean age: 39.6 years, 20 males) were smokers (> or = 10 cigarettes/day); 29 patients (mean age: 43.9 years, 7 males) were non-smokers. Full-mouth plaque (FMP) and bleeding on probing (BOP) scores, probing depth (PD), clinical attachment level (CAL), and recession depth (RD) were assessed immediately before and 6 months following surgery. Only sites with presurgery PD > or = 4 mm were used for statistical analysis. RESULTS: Presurgery FMP and BOP were similar in smokers and non-smokers and significantly decreased postsurgery in both groups. Overall, PD reduction and CAL gain were greater, although not significantly, in non-smokers (2.4 +/- 0.9 mm and 1.6 +/- 0.7 mm, respectively) than in smokers (1.9 +/- 0.7 mm and 1.2 +/- 0.7 mm, respectively). For moderate sites (PD 4 to 6 mm), no significant differences in PD and CAL changes were found between groups. For deep sites (PD > or = 7 mm), PD reduction was 3.0 +/- 1.0 mm in smokers and 4.0 +/- 0.8 mm in non-smokers, and CAL gain amounted to 1.8 +/- 1.1 mm in smokers and 2.8 +/- 1.0 mm in non-smokers (P = 0.0477). In smokers, 16% of deep sites healed to postsurgery PD values < or = 3 mm as compared to 47% in non-smokers (P = 0.0000); 58% of deep sites in smokers showed a CAL gain > or = 2 mm, as compared to 82% in non-smokers (P = 0.0000). CONCLUSIONS: Results of the study indicated that: 1) FDS determined a statistically significant PD reduction and CAL gain in patients with moderate to advanced periodontitis; 2) smokers exhibited a trend towards less favorable healing response following FDS compared to non-smokers, both in terms of PD reduction and CAL gain; and 3) this trend reached clinical and statistical significance at sites with initial deep PD.

An in vitro screening model to evaluate root conditioning protocols for periodontal regenerative procedures.

BACKGROUND: Preclinical studies have shown that the condition of the root surface may play a decisive role for outcome of wound healing between a mucogingival flap and a denuded root surface. Root surface demineralization has been shown to promote the establishment of a new connective tissue attachment. Conversely, root conditioning with extracellular matrix proteins or fluorides has produced outcomes characterized by a long junctional epithelium. Collectively, present evidence suggests that early events in the healing sequel; i.e., the adsorption and adhesion of blood elements to the root surface are critical for outcomes of wound healing between a mucogingival flap and a denuded root surface. Ultimately understanding and control of these events are vital for successful design and execution of periodontal regenerative protocols, particularly those involving root conditioning. Consequently, the objective of this study was to develop a screening model for immediate evaluation of the influence of root conditioning protocols on the adsorption and adhesion of blood to dentin surfaces. METHODS: Planed and citric acid-treated human dentin surfaces were exposed to fresh blood allowed to clot and were then rinsed before scanning electron microscopy evaluation. RESULTS: Citric acid treated planed dentin surfaces presented a thick network of fibrin directly attaching to the dentin surface entrapping cellular elements, mainly erythrocytes. In contrast, untreated, planed dentin exhibited an amorphous appearance with sparse strands of adsorbed fibrous proteins and few adherent erythrocytes. CONCLUSIONS: This in vitro screening model may effectively distinguish dentin surfaces with potential for enhanced adsorption and adhesion of blood elements. Periodontal regenerative protocols involving root conditioning unsuccessful in maintaining the experimentally imposed fibrin clot in this model may have lesser clinical significance than those that do.